The Encyclopedia britannica; a dictionary of arts, sciences, and general literatureWith new maps, and original American articles by eminent writersWith American revisions and additions, bringing each volume up to date . of en aggregation of numerous discoidallobes. Strictly arboreal in habits, vegetable feeders, and limitedgeographically to the forest regions of South and Central genera, Bradypus and Cholcepus. See Sloth. T. 858. EDENTATA.] MAMMALIA 385 botli North and South America, were Intormediate betv\-cen those ofthe existing Bradypodidx luid the Myrmccopfiarjidiv, combining
The Encyclopedia britannica; a dictionary of arts, sciences, and general literatureWith new maps, and original American articles by eminent writersWith American revisions and additions, bringing each volume up to date . of en aggregation of numerous discoidallobes. Strictly arboreal in habits, vegetable feeders, and limitedgeographically to the forest regions of South and Central genera, Bradypus and Cholcepus. See Sloth. T. 858. EDENTATA.] MAMMALIA 385 botli North and South America, were Intormediate betv\-cen those ofthe existing Bradypodidx luid the Myrmccopfiarjidiv, combining tliohead and dentition of the former with the structure of the vertebralcolumn, limbs, and tail of iho latter. Almost all the known sjieciesare of comparatively gigantic size, tlio smallest, Ccelodon csciivan- xisis, exceeding the largest existing Antcater, and the Megatlierium,being larger than a Rhiuoceros. TlieduntiLion is usually -J on each. f: 2 d Tio. 35.—Section of Upper Molar Teeth of Mcq side, as in the Sloths, but in Ccelodon $. Tliis genus, and in q stillmore marked degree Megatherium, differ from all tho others in thedetails of the structure of the teeth. They are very deeplyimplanted, of prismatic form (quadrate in transverse section); andthe component tissues—hard dentine (fig. 35, d), softer vaso-dentine{v), and cementum(c)—are so arrangedthat, as the tooth wears, the surfacealways presents a pair of transverseridges, thus producing a trituratingapparatus comparable to the bilopho-dout raolar of Dinodtcriitm, TapiritSyMariatus, Macropus, and others, thoughproduced in a different manner. In allthe other genera the teeth are more orless cylindrical, though sometimes later-ally compressed or even longitudinallygroope-d on the sides, and on the grind-ing surface the prominent ridge of harddentine follows the external contour,and is surrounded only by a thin layerof cementum, as in the existing gene
Size: 1606px × 1556px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorbaynesth, bookcentury1800, bookdecade1890, bookyear1892
